Someone who has experienced being homeless recently said to me: "The point of intervention has to come when someone calls for help." All too often that comes to late; vulnerable people only get the help they need when they have hit rock bottom. "You're already in a bad position, but you find it has to get worse so you can fit into a box to actually get help," he explained.

It was with some anticipation that we awaited the publication of Making Every Contact Count, the government's long-awaited strategy for preventing homelessness.

Research from Heriot Watt University has shown that six out of 10 adults using homelessness and other specialist services have spent time in prison, social care or other institutions before becoming homeless. Before people seek help from homelessness agencies, individuals have often already been in long-term contact with mental health, drug, criminal justice or social care services. Our own research shows that over half of new rough sleepers will have approached other services for help before they sleep rough.

So what will it take to prevent it? Can we really prevent homelessness before it happens? I think we can. We know that homelessness can be avoided if the right safety nets are in place. But we also know that half of people who become homeless wouldn't have known where to go for help, even if it was available.

Better information might have helped some, but that isn't the best we can do for someone facing crisis. The onus has to be on agencies from across the public and voluntary sectors taking local responsibility.

It's a cast of thousands: to prevent homelessness we need police, probation officers, nurses, doctors, teachers, prison officers, librarians and others to see this as part of their job. We also need government departments to "homeless proof" their policies.

The vision behind Making Every Contact Count is bold; by taking an integrated approach, we can prevent homelessness. For those of us working to close the door on homelessness, it is a welcome message.

As the title suggests, the paper stresses the need to make good use of every contact agencies have with people who are at risk of homelessness, setting out 10 challenges for local authorities. It asks that prevention of homelessness is made the business of all local services. It challenges council housing departments to provide their prevention advice in writing so that individuals are clear about the advice and assistance offered.

But achieving this "gold standard" demands a clear understanding of homeless people. It demands better recording of people's housing status whenever they use public or voluntary sector services. Most importantly, it demands some way of challenging and holding to account the services that just aren't delivering on this ambition.

If we really can make every contact with all agencies count, as this paper aims, then it will be a big step towards effective prevention. But this bold vision will be undermined if policies elsewhere, such as welfare reform, lead to increased homelessness. With homelessness services facing an average funding cut of 15% last year, progress will also be hampered if there is not the local commitment to protect the very services that are critical to preventing homelessness.

And we need more than the government has commited so far. We need clearer national action from policymakers outside the Department for Communities and Local Government. While there are some encouraging signs, such as the Department of Health's commitment to improve the way the NHS handles homeless people who access acute services, I would like to see more from other government departments. We will also need more innovation on the frontline.

Last July, the government published its vision to end rough sleeping. This strategy, along with £20m in funding for innovative new ways to stop people sleeping on the streets, is already having an impact across the country. Just this week, £3.5m in homelessness transition fund grants were announced for 21 projects – including eight to put services in place to prevent new rough sleepers spending more than a single night out.

Together, we need to make the vision in this paper more than just a vision.

I believe that, by being ready to work together, local and national government and the voluntary sector will be able to call a halt to the rise in homelessness and stop vulnerable people becoming the rough sleepers of the future.